1. Field of the Invention
The invention relates to a sports apparatus whose degree and direction of stiffness and flexibility may be varied.
2. Discussion of Related Art
In recent years, sports equipment manufacturers have increasingly turned to different kinds of materials to enhance their sporting equipment. In so doing, entire lines of sports equipment have been developed whose stiffness or flexibility characteristics are but a shade different from each other. Such a shade of difference, however, may be enough to give the sports equipment user an edge over the competition or enhance sports performance.
With such a selection and variety of sports equipment available, the sports equipment user may train with equipment with different stiffness or flexibility characteristics as desired and, during play, may switch to sports equipment that is slightly more flexible or stiffer to suit changing playing conditions or to help compensate for weariness or fatigue.
Nevertheless, there are limitations. Subtle changes in the stiffness or flexibility characteristics of sports equipment may not be available between different pieces of sports equipment. This is due to the characteristics being fixed by the manufacturer because of the choice of materials, design, etc.
A sports player desiring to change the lift in a sports object being struck with a striking surface of sports equipment may prefer a more flexible or stiffer characteristic.
Turning to various types of sports, it can be seen how the lack of adjustability in stiffness and flexibility may adversely affect optimum performance of the player.
HOCKEY
Hockey includes, but is not limited to, ice hockey, street hockey, roller hockey, field hockey and floor hockey.
Hockey players may require that the flexure of the hockey stick be changed to better assist in the wrist shot or slap shot needed at that particular junction of a game or which the player was better at making. Younger players may require more flex in the hockey stick due to lack of strength; such flex may mean the difference between the younger player being able to lift the puck or not when making a shot since a stiffer flex in the stick may not allow the player to achieve such lift.
In addition, as the younger players ages and increases in strength, the player may desire a stiffer hockey stick, which in accordance with convention means the hockey player would need to purchase additional hockey stick shafts with the desired stiffness and flexibility characteristics. Indeed, to cover a full range of nuances of differing stiffness and flexibility characteristics, hockey players would have available many different types of hockey sticks.
Even so, the hockey player may merely want to make a slight adjustment to the stiffness or flexibility of a given hockey stick to improve the nuances of the play. Such would not be possible unless the multitude of hockey sticks included those having all such slight variations in stiffness and flexibility needed to facility such nuances.
TENNIS
Tennis players also may want some adjustability in their tennis rackets. Tennis rackets include those which allow the handle to rotate relative to the racket shaft, such as disclosed in U.S. Pat. No. 5,409,216 (hereinafter the '216 patent), to improving the grip on the handle while performing various tennis shots. In the case where the shaft is in the form of double head ends as also shown in the '216 patent, the result may be a change in the stiffness or flexibility of the racket due to a change in orientation of the double head ends relative to the racket head.
Although tennis players may be comfortable with the grip afforded by such a handle, they may desire a stiffer or more flexible racket, particularly so as the tennis player becomes more weary during play. Such would not be possible without sacrificing the comfortable grip, unless the tennis player were equipped with a multitude of tennis rackets to choose from, each varying slightly as concerns stiffness and flexibility.
LACROSSE
Lacrosse players use their lacrosse sticks to scoop up a lacrosse ball and pass the ball to other players or toward goal. The stiffness or flexibility of the lacrosse stick may affect performance during the game. Players may tire so some adjustment to the flexibility of the stick may be desired to compensate. With conventional lacrosse sticks, such adjustment is not available.
OTHER RACKET SPORTS
Other types of racket sports also suffer from the drawback of being unable to vary the stiffness and flexibility of the racket during the course of play to suit the needs of the player at that time, whether those needs arise from weariness, desired field positions, or training for improvement. Such racket sports include racquetball, paddleball, squash, badminton, and court tennis.
For conventional rackets, the stiffness and flexibility is set by the manufacturer and invariable. If the player tires of such characteristics being fixed or otherwise wants to vary the stiffness and flexibility, the only practical recourse is to switch to a different racket whose stiffness and flexibility characteristics better suit the needs of the player at that time.
GOLF
Golf clubs may be formed of graphite, wood, titanium, glass fiber or various types of composites or metal alloys. Each varies to some degree with respect to stiffness and flexibility. However, golfers generally carry onto the golf course only a predetermined number of golf clubs for driving. Varying the stiffness or flexibility of the golf club is not possible, unless the golfer brings another set of clubs of a different construction. Even in that case, however, the selection is still somewhat limited.
Nevertheless, it is impractical to carry a huge number of golf clubs onto the course, each club having a slight nuance of difference in flexibility and stiffness than another. Golf players prefer taking onto the course a set of clubs that are suited to the player's specific swing type, strength and ability.
SKIING
Skis are made from a multitude of different types of materials and dimensions, the strength and flexibility of each type differing to a certain extent. Skis include those for downhill ice skiing, cross-country skiing and water-skiing. Other types of snow sports devices include snowboards, snow skates and skiboards. Beginners generally require more flex and, as they progress in ability, much less.
Skiers generally do not carry with them a multitude of different types of skis for themselves use during the course of the day to suit changing skiing conditions or to compensate for their own weariness during the day. The same holds true for those who use snowboards, snow skates and skiboards.
BATTING
Sports such as baseball, softball, and cricket use bats to strike a ball. The batter may want to select a bat that is more stiff or flexible, depending upon the circumstances of play. Conventional bats only permit the batter to choose from among a variety of bats of different weights and materials to obtain the desired stiffness or flexibility. However, adjusting the stiffness or flexibility characteristics for a given bat is not feasible conventionally. Further, there is no practical way conventionally to determine which batting flexure and stiffness is optimal for batters with a single batting device.
POLO
Polo players use mallets during the course of the polo match. Changing the stiffness or flexibility characteristics is only available by exchanging for a different mallet with the desired characteristics.
SAILBOATING and SAILBOARDING
Masts of sailboats and sailboards support sails, which are subjected to wind forces. These wind forces, therefore, act through the sails on the mast. The mast may be either a rigid or flexible structure, which may be more desirable under certain sailing conditions. If the mast is flexible, tension wires may be used to vary the tension of the mast. Otherwise, the flexibility and stiffness characteristics of mast are generally fixed by the manufacturer, making it impractical to alter the mast flexibility or stiffness in different directions to suit changes in wind direction or the needs of the sailor.
CANOEING, ROWBOATING and KAYAKING
Paddles for canoes, row boats, and kayaks are subjected to forces as they are stroked through water. The flexibility or stiffness of the paddles, while different depending upon its design and materials, is fixed by the manufacturer. Thus, a rower who desired to change such characteristics would need to switch to a different type of paddle. Carrying a multitude of different types of paddles for use with a canoe, row boat or kayak, however, is generally impractical for the typical rower from the standpoint of cost, bulk and storage.
POLE VAULTING
Pole vaulters use a pole to lift themselves to desired heights. The pole has flexibility and stiffness characteristics to assist in attaining this goal. Varying those characteristics, however, requires switching to a different pole, because such characteristics are generally fixed by the manufacturer.
As defined in this application, sports equipment covers any type of stick, bat, racket, club, ski, board, mast, pole, skate, paddle or mallet that is used in sports, except for fishing rods. Fishing rods are unique in that they are flexed for casting out a line; none of the other types of equipment mentioned in this application for sports equipment is used to cast out a line or the like. Instead, they flex to strike or pick up and carry an object such as a ball or puck (hockey, lacrosse, batting, golf, tennis, etc.) or to carry a person (pole vaulting), flex in response to engaging a frictional surface such as skis against the ground, snow or water, or flex in response to environmental forces such as the wind against a sail.